function Person (){
    this.name = 'Person'
    this.age = 19
    this.getAge = function(){
        return this.age
    }
}

const p1 = new Person()
const a = p2.getAge()

function Person1 (){
    this.name = 'Person'
    this.age = 19
}
const p2 = new Person1()
const b = p2.age
// Jsperf上查看运行速度